Reenforced steel plate



. apex of vcontour by unirsi@ scares Parana ottica.

RY A. NELSON, 0F CHICAGO, ELINOIS.

nnnnroncnn STEEL PLATE.

To altwhom it may cof/wem: l

Be it known that I ROY A. NELSON, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Reenforced SteelPlates, of which the following is a specification.

The object of simple, strong, expensive means doors (such as are used onthe like), panel steel-floors, partitions and similar devices, so thatthey will easily and effectually withstand all necessary stress.

My invention consists of certain details of construction hereinafter setforth, pointed out in my claim and illustrated in the accompanyingdrawings, in which:

Fig. 1 shows a portion of the side of a freight car and an all-steeldoor, made in accordance with my invention;

Fig; 2 shows an enlarged detail view of a ortion of the same; and

ig. 8 shows a detail view line 3-3 of Fig. 1.

Referring to the accompanying drawings, the reference numerals 10 and 11are used to indicate two mating sheets of metal` designed to be rivetedor otherwise joined together. These metal sheets are placed in acompress and stamped with corrugations such as shown by the numerals 12`13, 14 and 15. The numeral 15 indicates an endless corrugation,preferably circular in conformation, stamped centrally in the sheetmetaldoor, or other and simpler object, andthe numeralsl, 13 and 14 indicatecorrugations radiating therefrom to the outer edge of the sheet metaldoor. The radiating corrugations join the central circular corrugationas shown, the apex of the radiating corrugation mating with or not.extending beyond the the circular corrugation. the lnner surface of thecircular corrugation being perfectly smooth and undisturbed im its thejoining of any other corrumy invention is to provide durable andpractically 1nfor strengthening all-steel taken on the gation. c l

The steel door, or other object, may be made of one piece of sheet metalstamped in this way, or it may be made up of a plurality of mating metalsheets which will be completed door,

freight cars and Specication-of Letters Patent. Patgqgntd Aug. 29, 1922Application filed August 11, 1919. Serial No. 316,539.

- metal. rThe corrugations may be stamped in the individual parts thatgo to make up one complete door before the parts are joined togetlier,or they may be stamped subsequently to their joining wlthout effectingmy invention, the principal feature of which is to provide a circularcorrugation centrally in the or other object, with radiatingcorrugations extending therefrom, as shown.

In ractical construction it has been establis ed that a door, or otherobject so constructed, will be able to withstand great stress, becauseeach radiating corrugation ending in the circular corrugation whichjoins them all, will assist each and every corrugation in performing itsfunction of providing strength. In such a construction there are nocrossing intersections between the corrugations, such as has been foundby the experiments and tests to make a weak point at the point ofintersection. By my construction, all intersections are avoided and thecircular central corrugation establishes and preserves the continuity ofall the radiating corrugations.

It is also obvious that instead of a circular corrugation centrallyofthe plate, a corrugation of any conformation which is continuous andendless into' which the radiating corrugations enter, in a mannersimilar to that shown in the drawings, may be used Without in any wavchanging my invention, the object. of which is to provide in asubstantially central location in the plate, an endless and continuouscorrugation from which lateral corrugat-ions may radiate.

Having thus described my invention. what I claim and desire to secure byLetters Patent of the nited States, is:

A sheet metal plate formed with an endless corrugation in its centralportion with corrugations radiating therefrom to points adjacent theouter edges of said plate, the radiating corrugations being ofsubstantially the same height as the central corrugation.

ln testimony whereof ll have signed the foregoing specification.

. ROY A. NELSON.

